Circular layouts are among the most prominent and oldest conventions used to draw graphs. This drawing convention is often used for the layout of networks and systems management diagrams, where it naturally captures the essence of ring and star topologies. It may be also used for other kinds of graphs, such as social networks and WWW graphs. In particular, a circular layout is appropriate for applications that emphasize the clustering decomposition of a graph, where each cluster is drawn on a separate circle.
In circular layouts, nodes are drawn on a circle, while the edges connecting these nodes are line segments passing within the circle. In general, these layouts may provide a compact presentation, focusing on individual nodes and edges. Additionally, well-designed circular layouts sometimes reveal global properties of the graph such as symmetries and patterns of collective behavior. Unfortunately, strong regularity can obscure other information. For example, circular layout drawings can be very dense, and following paths on them can be difficult.